Method and apparatus for mitigating interference in femtocell deployments

ABSTRACT

Methods and apparatuses are provided for determining one or more parameters of an access point that can be set or adjusted to mitigate interference to other access points. A rise-over-thermal (RoT) threshold can be set at an access point based on one or more parameters, such as pathloss measurements, location of the access point, etc., such that interference from devices communicating with the access point can be mitigated. In addition, a noise floor, RoT threshold, etc., can be adjusted based on determining a transmit power difference, out-of-cell interference, and/or similar measurements.

CLAIM OF PRIORITY UNDER 35 U.S.C. §119

The present Application for Patent claims priority to ProvisionalApplication No. 61/359,762 entitled “ADAPTIVE RISE-OVER-THERMAL (ROT)THRESHOLD AND NOISE FLOOR ADJUSTMENT FOR FEMTOCELL UPLINK INTERFERENCEMANAGEMENT” filed Jun. 29, 2010, and assigned to the assignee hereof andhereby expressly incorporated by reference herein, as well asProvisional Application No. 61/387,359 entitled “ADAPTIVERISE-OVER-THERMAL (ROT) THRESHOLD AND NOISE FLOOR ADJUSTMENT FORFEMTOCELL UPLINK INTERFERENCE MANAGEMENT” filed Sep. 28, 2010, andassigned to the assignee hereof and hereby expressly incorporated byreference herein.

BACKGROUND

1. Field

The following description relates generally to wireless networkcommunications, and more particularly to mitigating interference infemtocell deployments.

2. Background

Wireless communication systems are widely deployed to provide varioustypes of communication content such as, for example, voice, data, and soon. Typical wireless communication systems may be multiple-accesssystems capable of supporting communication with multiple users bysharing available system resources (e.g., bandwidth, transmit power, . .. ). Examples of such multiple-access systems may include code divisionmultiple access (CDMA) systems, time division multiple access (TDMA)systems, frequency division multiple access (FDMA) systems, orthogonalfrequency division multiple access (OFDMA) systems, and the like.Additionally, the systems can conform to specifications such as thirdgeneration partnership project (3GPP), 3GPP long term evolution (LTE),ultra mobile broadband (UMB), evolution data optimized (EV-DO), etc.

Generally, wireless multiple-access communication systems maysimultaneously support communication for multiple mobile devices. Eachmobile device may communicate with one or more access points viatransmissions on forward and reverse links. The forward link (ordownlink) refers to the communication link from access points to mobiledevices, and the reverse link (or uplink) refers to the communicationlink from mobile devices to access points. Further, communicationsbetween mobile devices and access points may be established viasingle-input single-output (SISO) systems, multiple-input single-output(MISO) systems, multiple-input multiple-output (MIMO) systems, and soforth. In addition, mobile devices can communicate with other mobiledevices (and/or access points with other access points) in peer-to-peerwireless network configurations.

To supplement conventional base stations, additional restricted accesspoints can be deployed to provide more robust wireless coverage tomobile devices. For example, wireless relay stations and low power basestations (e.g., which can be commonly referred to as Home NodeBs or HomeeNBs, collectively referred to as H(e)NBs, femto access points,femtocells, picocells, microcells, etc.) can be deployed for incrementalcapacity growth, richer user experience, in-building or other specificgeographic coverage, and/or the like. In some configurations, such lowpower base stations can be connected to the Internet via broadbandconnection (e.g., digital subscriber line (DSL) router, cable or othermodem, etc.), which can provide the backhaul link to the mobileoperator's network. Thus, for example, the low power base stations canbe deployed in user homes to provide mobile network access to one ormore devices via the broadband connection.

In this regard, deployment of such low power base stations is unplannedin many cases, and thus the base stations and/or mobile devicescommunicating therewith can cause interference to other low power basestations, macrocell base stations, or other devices in the vicinity.Interference mitigation mechanisms exist for low power base stations toset transmission power thereof preventing or lessening interference withother access points. Devices served by the low power access point,however, can still cause interference to the other access points.

SUMMARY

The following presents a simplified summary of one or more aspects inorder to provide a basic understanding of such aspects. This summary isnot an extensive overview of all contemplated aspects, and is intendedto neither identify key or critical elements of all aspects nordelineate the scope of any or all aspects. Its sole purpose is topresent some concepts of one or more aspects in a simplified form as aprelude to the more detailed description that is presented later.

In accordance with one or more embodiments and corresponding disclosurethereof, various aspects are described in connection with modifyingparameters of a femtocell access point to mitigate interference with oneor more other access points in the vicinity. For example, arise-over-thermal (RoT) threshold can be set for the femtocell accesspoint based at least in part on one or more parameters related to amacrocell within which the femtocell access point communicates tomitigate interference to an access point of the macrocell and/or one ormore other femtocell access points. In one example, the RoT thresholdcan be determined based at least in part on one or more pathlossmeasurements received from one or more devices communicating with thefemtocell access point (e.g., pathloss to the femtocell access point, toone or more macrocell or other femtocell access points, and/or thelike). Moreover, in another example, a femtocell access point canincrease a noise floor to mitigate interference from one or more otheraccess points or devices communicating therewith (e.g., based at leastin part on detecting a signal strength of the one or more other accesspoints, out-of-cell interference etc.).

According to an example, a method for setting a RoT threshold for afemtocell access point is provided. The method includes receiving one ormore parameters corresponding to one or more access points, determininga RoT threshold for the femtocell access point based at least in part onthe one or more parameters. The method also includes setting the RoTthreshold at the femtocell access point.

In another aspect, an apparatus for setting a RoT threshold for afemtocell access point is provided. The apparatus includes at least oneprocessor configured to receive one or more parameters corresponding toone or more access points and determine a RoT threshold for thefemtocell access point based at least in part on the one or moreparameters. The at least one processor is further configured to set theRoT threshold at the femtocell access point. The apparatus also includesa memory coupled to the at least one processor.

In yet another aspect, an apparatus for setting a RoT threshold for afemtocell access point is provided that includes means for receiving oneor more parameters corresponding to one or more access points and meansfor determining a RoT threshold for the femtocell access point based atleast in part on the one or more parameters. The apparatus furtherincludes means for setting the RoT threshold at the femtocell accesspoint.

Still, in another aspect, a computer-program product for setting a RoTthreshold for a femtocell access point is provided including acomputer-readable medium having code for causing at least one computerto receive one or more parameters corresponding to one or more accesspoints and code for causing the at least one computer to determine a RoTthreshold for the femtocell access point based at least in part on theone or more parameters. The computer-readable medium further includescode for causing the at least one computer to set the RoT threshold atthe femtocell access point.

Moreover, in an aspect, an apparatus for setting a RoT threshold for afemtocell access point is provided that includes a parameter receivingcomponent for receiving one or more parameters corresponding to one ormore access points and a RoT threshold determining component fordetermining a RoT threshold for the femtocell access point based atleast in part on the one or more parameters. The apparatus furtherincludes a RoT threshold setting component for setting the RoT thresholdat the femtocell access point.

According to another example, a method for adjusting parameters of anaccess point based on determining interference is provided. The methodincludes detecting a strongest transmit power of one or more accesspoints and determining whether the strongest transmit power exceeds atransmit power utilized at a femtocell access point. The method furtherincludes adjusting an estimated noise floor of the femtocell accesspoint based at least in part on whether the strongest transmit powerexceeds the transmit power.

In another aspect, an apparatus for adjusting parameters of an accesspoint based on determining interference is provided. The apparatusincludes at least one processor configured to detect a strongesttransmit power of one or more access points and determine whether thestrongest transmit power exceeds a transmit power utilized at afemtocell access point. The at least one processor is further configuredto adjust a noise floor of the femtocell access point based at least inpart on whether the strongest transmit power exceeds the transmit power.The apparatus also includes a memory coupled to the at least oneprocessor.

In yet another aspect, an apparatus for adjusting parameters of anaccess point based on determining interference is provided that includesmeans for detecting a strongest transmit power of one or more accesspoints and means for adjusting a noise floor of a femtocell access pointbased at least in part on determining whether the strongest transmitpower exceeds a transmit power of the femtocell access point.

Still, in another aspect, a computer-program product for adjustingparameters of an access point based on determining interferences isprovided including a computer-readable medium having code for causing atleast one computer to detect a strongest transmit power of one or moreaccess points and code for causing the at least one computer todetermine whether the strongest transmit power exceeds a transmit powerutilized at a femtocell access point. The computer-readable mediumfurther includes code for causing the at least one computer to adjust anoise floor of the femtocell access point based at least in part onwhether the strongest transmit power exceeds the transmit power.

Moreover, in an aspect, an apparatus for adjusting parameters of anaccess point based on determining interference is provided that includesan interference determining component for detecting a strongest transmitpower of one or more access points and a noise floor adjusting componentfor adjusting a noise floor of a femtocell access point based at leastin part on determining whether the strongest transmit power exceeds atransmit power of the femtocell access point.

To the accomplishment of the foregoing and related ends, the one or moreaspects comprise the features hereinafter fully described andparticularly pointed out in the claims. The following description andthe annexed drawings set forth in detail certain illustrative featuresof the one or more aspects. These features are indicative, however, ofbut a few of the various ways in which the principles of various aspectsmay be employed, and this description is intended to include all suchaspects and their equivalents.

BRIEF DESCRIPTION OF THE DRAWINGS

The disclosed aspects will hereinafter be described in conjunction withthe appended drawings, provided to illustrate and not to limit thedisclosed aspects, wherein like designations denote like elements, andin which:

FIG. 1 is a block diagram of an example system that facilitatesmitigating interference in a wireless network.

FIG. 2 is a block diagram of an example system for determining arise-over-thermal (RoT) threshold for mitigating device interference toother access points.

FIG. 3 is a block diagram of an example system for requesting pathlossmeasurements from one or more devices.

FIG. 4 is a block diagram of an example system for adjusting a noisefloor or other parameters of an access point.

FIG. 5 is a flow chart of an aspect of an example methodology fordetermining a RoT threshold for an access point.

FIG. 6 is a flow chart of an aspect of an example methodology thatdetermines a RoT threshold based on a transmit power.

FIG. 7 is a flow chart of an aspect of an example methodology thatdetermines a RoT threshold using a pathloss difference CDF.

FIG. 8 is a flow chart of an aspect of an example methodology foradjusting a noise floor at an access point.

FIG. 9 is a flow chart of an aspect of an example methodology thatenforces estimated noise floor for devices in soft handover.

FIG. 10 is a block diagram of an example mobile device according tovarious aspects described herein.

FIG. 11 is a block diagram of an example system for adjusting one ormore parameters of an access point.

FIG. 12 is a block diagram of an example system that determines a RoTthreshold for an access point.

FIG. 13 is a block diagram of an example system that enforces estimatednoise floor for devices in soft handover.

FIG. 14 is a block diagram of an example wireless communication systemin accordance with various aspects set forth herein.

FIG. 15 is an illustration of an example wireless network environmentthat can be employed in conjunction with the various systems and methodsdescribed herein.

FIG. 16 illustrates an example wireless communication system, configuredto support a number of devices, in which the aspects herein can beimplemented.

FIG. 17 is an illustration of an exemplary communication system toenable deployment of femtocells within a network environment.

FIG. 18 illustrates an example of a coverage map having several definedtracking areas.

DETAILED DESCRIPTION

Various aspects are now described with reference to the drawings. In thefollowing description, for purposes of explanation, numerous specificdetails are set forth in order to provide a thorough understanding ofone or more aspects. It may be evident, however, that such aspect(s) maybe practiced without these specific details.

As described further herein, one or more parameters of a femtocellaccess point can be set or adjusted to mitigate interference to one ormore other access points (e.g., potentially caused by devicescommunicating with the femtocell access point). For example, arise-over-thermal (RoT) threshold of the femtocell access point can beset and/or adjusted based on one or more parameters related to an accesspoint within which the femtocell access point communicates. In oneexample, the one or more parameters can be a pathloss to the femtocellaccess point, one or more other femtocell access points or macrocellaccess points, and/or the like. In another example, an estimated noisefloor of an access point can be adjusted based on a determined level ofinterference caused to the access point. In either case, the adjustmentscan result in modifications to utilized power by devices communicatingtherewith, which can mitigate interference caused at or caused by one ormore access points.

As used in this application, the terms “component,” “module,” “system”and the like are intended to include a computer-related entity, such asbut not limited to hardware, firmware, a combination of hardware andsoftware, software, or software in execution. For example, a componentmay be, but is not limited to being, a process running on a processor, aprocessor, an object, an executable, a thread of execution, a program,and/or a computer. By way of illustration, both an application runningon a computing device and the computing device can be a component. Oneor more components can reside within a process and/or thread ofexecution and a component may be localized on one computer and/ordistributed between two or more computers. In addition, these componentscan execute from various computer readable media having various datastructures stored thereon. The components may communicate by way oflocal and/or remote processes such as in accordance with a signal havingone or more data packets, such as data from one component interactingwith another component in a local system, distributed system, and/oracross a network such as the Internet with other systems by way of thesignal.

Furthermore, various aspects are described herein in connection with aterminal, which can be a wired terminal or a wireless terminal. Aterminal can also be called a system, device, subscriber unit,subscriber station, mobile station, mobile, mobile device, remotestation, remote terminal, access terminal, user terminal, terminal,communication device, user agent, user device, or user equipment (UE). Awireless terminal may be a cellular telephone, a satellite phone, acordless telephone, a Session Initiation Protocol (SIP) phone, awireless local loop (WLL) station, a personal digital assistant (PDA), ahandheld device having wireless connection capability, a computingdevice, or other processing devices connected to a wireless modem.Moreover, various aspects are described herein in connection with a basestation. A base station may be utilized for communicating with wirelessterminal(s) and may also be referred to as an access point, a Node B,evolved Node B (eNB), H(e)NB, or some other terminology.

Moreover, the term “or” is intended to mean an inclusive “or” ratherthan an exclusive “or.” That is, unless specified otherwise, or clearfrom the context, the phrase “X employs A or B” is intended to mean anyof the natural inclusive permutations. That is, the phrase “X employs Aor B” is satisfied by any of the following instances: X employs A; Xemploys B; or X employs both A and B. In addition, the articles “a” and“an” as used in this application and the appended claims shouldgenerally be construed to mean “one or more” unless specified otherwiseor clear from the context to be directed to a singular form.

The techniques described herein may be used for various wirelesscommunication systems such as CDMA, TDMA, FDMA, OFDMA, SC-FDMA and othersystems. The terms “system” and “network” are often usedinterchangeably. A CDMA system may implement a radio technology such asUniversal Terrestrial Radio Access (UTRA), cdma2000, etc. UTRA includesWideband-CDMA (W-CDMA) and other variants of CDMA. Further, cdma2000covers IS-2000, IS-95 and IS-856 standards. A TDMA system may implementa radio technology such as Global System for Mobile Communications(GSM). An OFDMA system may implement a radio technology such as EvolvedUTRA (E-UTRA), Ultra Mobile Broadband (UMB), IEEE 802.11 (Wi-Fi), IEEE802.16 (WiMAX), IEEE 802.20, Flash-OFDM®, etc. UTRA and E-UTRA are partof Universal Mobile Telecommunication System (UMTS). 3GPP Long TermEvolution (LTE) is a release of UMTS that uses E-UTRA, which employsOFDMA on the downlink and SC-FDMA on the uplink. UTRA, E-UTRA, UMTS, LTEand GSM are described in documents from an organization named “3rdGeneration Partnership Project” (3GPP). Additionally, cdma2000 and UMBare described in documents from an organization named “3rd GenerationPartnership Project 2” (3GPP2). Further, such wireless communicationsystems may additionally include peer-to-peer (e.g., mobile-to-mobile)ad hoc network systems often using unpaired unlicensed spectrums, 802.xxwireless LAN, BLUETOOTH and any other short- or long- range, wirelesscommunication techniques.

Various aspects or features will be presented in terms of systems thatmay include a number of devices, components, modules, and the like. Itis to be understood and appreciated that the various systems may includeadditional devices, components, modules, etc. and/or may not include allof the devices, components, modules etc. discussed in connection withthe figures. A combination of these approaches may also be used.

Referring to FIG. 1, an example wireless communication system 100 isillustrated that facilitates setting one or more parameters at a servingaccess point to mitigate interference to other access points. System 100comprises a device 102 that can communicate with a serving access point104 to receive access to a wireless network and/or one or morecomponents thereof. System 100 can also comprise other access points 106and/or 108 with which device 102 can potentially interfere. System 100also optionally comprises another device 110 that can be served byserving access point 104. For example, device 102 and/or 110 can be aUE, modem (or other tethered device), a portion thereof, and/or thelike. Access points 104, 106, and/or 108 can each be a femtocell accesspoint (such as a Home Node B or Home evolved Node B, collectivelyreferred to herein as H(e)NB), picocell access point, microcell accesspoint, a mobile base station, a relay node, a device (e.g.,communicating in peer-to-peer or ad-hoc mode), a portion thereof, and/orthe like.

According to an example, device 102 can potentially interfere withaccess point 106 and/or 108 while transmitting signals 112 (whetherreporting pathloss or otherwise) to serving access point 104. Asdescribed, at least some of serving access point 104, access point 106,and/or access point 108 can be part of a femtocell or other unplannedwireless network deployment, and thus, the access points 104, 106,and/or 108, or devices communicating therewith, can possibly interferewith one another (e.g., where access points are deployed in closeproximity). In this regard, for example, serving access point 104 canset or adjust one or more parameters to mitigate the possibleinterference caused by device 102 and/or other devices.

As described further herein, serving access point 104 can set a RoTthreshold based at least in part on one or more communication parametersto mitigate interference to access points 106 and/or 108. In oneexample, the one or more communication parameters can correspond topathloss measurements to the access points 106 and/or 108 along with apathloss to serving access point 104, as computed by device 102, one ormore other devices, such as device 110, a network listening module (NLM)of serving access point (not shown), and/or the like. The RoT thresholdcan additionally be set based at least in part on a determined noisefloor at the access points, etc. Thus, for example, device 102 canreport pathloss measurements 112 to serving access point 104 based atleast in part on computing pathloss to serving access point based onsignal 114, pathloss to access point 106 based on receiving signal 116,and/or the like. In another example, the one or more parameters cancorrespond to parameters from which a pathloss can be determined, suchas a received signal code power (RSCP), a common pilot indicator channel(CPICH) transmit power in LTE, and/or the like.

In another example, serving access point and access point 106 (and/oraccess point 108) can utilize different transmission powers, which canresult in device 102 communicating with an access point 104 thatoperates at a greater distance, but transmits using a higher power thanaccess point 106. In this example, the device 102 can thus interferewith access point 106 when communicating with serving access point 104at the higher power. To mitigate such interference, for example, accesspoint 106 can adjust a RoT threshold and/or noise floor to increasetransmission power used by devices communicating therewith. In thisexample, access point 106 can obtain transmission power 118 of servingaccess point 104 and/or other neighboring access points (not shown) atleast in part by using an NLM or other device, receiving an indicationof power from the serving access point 104, and/or the like. Accesspoint 106 can adjust an noise floor by a difference in transmissionpower between access point 106 and serving access point 104. In anotherexample, access point 106 can adaptively adjust the noise floor or a RoTthreshold based at least in part on the difference.

In yet another example, device 102 can communicate simultaneously withserving access point 104 and access point 106 (e.g., in soft handover(SHO)) such that device 102 communicates control data with servingaccess point 104 and receives user plane data from access point 106and/or serving access point 104. In this example, where access point 106utilizes a higher transmit power than serving access point 104, servingaccess point 104 may not be able to reliably receive control data fromdevice 102 since access point 106 can control power of device 102 aswell, as part of SHO. In this example, access point 106 can enforce theadjusted noise floor in communicating with device 102 (e.g., and notother devices that are not using SHO with access point 106 as theserving access point), which can cause device 102 to increasetransmission power so serving access point 104 can obtain control datatherefrom. The above modifications allow for managing interferencecaused by access points deployed in a wireless network.

Turning to FIG. 2, an example wireless communication system 200 isillustrated for setting a RoT threshold at an access point. System 200comprises a device 202 that communicates with a serving access point 204to receive access to one or more wireless network components, asdescribed. In addition, system 200 can include another access point 206with which device 202 can potentially interfere due at least in part tocommunicating with serving access point 204. For example, deployment ofserving access point 204 can result in interference to other accesspoints in the vicinity of serving access point 204 (not shown), whethercaused by serving access point 204, device 202 or other devicescommunicating with serving access point 204, etc. As described, forexample, device 202 can be a UE, modem, etc., and serving access point204 can be a femtocell access point, H(e)NB, and/or the like. Accesspoint 206, for example, can be a macrocell access point, femtocell orpicocell access point, mobile base station, relay, etc., as described.

Device 202 can optionally comprise a pathloss measuring component 208that determines a pathloss to one or more access points, and a pathlossreporting component 210 that communicates the determined pathloss to oneor more access points or devices. Serving access point 204 comprises aparameter receiving component 212 for obtaining one or more parametersrelated to a communication environment (e.g., communicating in amacrocell), a RoT threshold determining component 214 for determining anRoT threshold for serving access point based at least in part on the oneor more parameters, and a RoT threshold setting component 216 forutilizing the RoT threshold at serving access point 204. Serving accesspoint 204 can also optionally comprise a NLM component 218 for obtainingand processing one or more signals from one or more access points,and/or a pathloss difference computing component 220 for determining apathloss difference between serving access point 204 and one or moreother access points.

According to an example, parameter receiving component 212 can obtainone or more parameters related to one or more other access points withina range of serving access point 204, such as access point 206, or one ormore other femtocell, macrocell, or substantially any type of accesspoint. For example, this can correspond to one or more parametersregarding a communications environment near access point 206, a locationof access point 206 relative to serving access point 204, etc. Based atleast in part on the one or more parameters, for example, RoT thresholddetermining component 214 can determine a RoT threshold for servingaccess point 204 to mitigate interference to other access points (e.g.,caused by devices communicating with serving access point 204).Moreover, being within range of serving access point 204 or parametersmeasured within a range of serving access point 204 can refer to signalsfrom access point 206 being heard by serving access point 204, devicescommunicating with serving access point 204, such as device 202, etc.

For example, where a RoT threshold for serving access point 204 is at ahigh level, device 202 attempting to access the serving access point 204(e.g., attempting to access the random access channel (RACH) thereof)can increase transmission power to reach a signal-to-noise ratio (SNR)corresponding to the RoT threshold. This can, however, causeinterference to access point 206 when device 202 communicates withserving access point 204 using the transmission power. Using a high RoTthreshold, however, improves throughput for device 202 at serving accesspoint 204, and can improve resistance to interference from other devicescommunicating with other access points. Thus, using one or moreparameters regarding the communications environment of serving accesspoint 204, RoT threshold determining component 214 can determine an RoTthreshold for serving access point 204.

For example, where the one or more parameters comprise a location ofaccess points relative to serving access point 204 (e.g., and/or anabsolute location of serving access point 204 compared to that of accesspoint 206), RoT threshold determining component 214 can evaluate adistance between serving access point 204 and known locations of one ormore other access points. For example, parameter receiving component 212can receive locations of the one or more access points from an accesspoint management server, such as a home eNB management server, apositioning server, such as a serving mobile location center (SMLC),etc. (not shown), access point 206, device 202 or other devices, and/orthe like. In this example, RoT threshold determining component 214 cancompute a distance to the one or more access points based on location ofthe serving access point 204 (which can also be received from apositioning server, for example) and received location of the one ormore access points, such as access point 206, and can determine a RoTthreshold for serving access point 204 based on the computed distance tomitigate interference to the other access points. In one example, NLMcomponent 218 can obtain signals from access point 206, and candetermine a signal strength; parameter receiving component 212 canobtain the signal strength from NLM component 218, and RoT thresholddetermining component 214 can determine the RoT threshold for servingaccess point 204 additionally or alternatively based on the signalstrength to mitigate interference to access point 206.

In another example, device 202 can report pathloss measurements toserving access point 204 to facilitate determining a RoT threshold. Inthis example, pathloss measuring component 208 can measure pathloss toserving access point 204, one or more neighboring access points, such asaccess point 206, and/or the like, and pathloss reporting component 210can communicate the pathloss measurements to serving access point 204.Parameter receiving component 212 can obtain the pathloss measurements,and RoT threshold determining component 214 can determine a RoTthreshold for serving access point 204 based at least in part on thepathloss measurements. For example, SNR at serving access point 204 fordevice 202 communicating therewith (e.g., trying to access a RACH) canbe:

γ_(RACH)=TxPwr_(F) −PL _(F)−(RoT+No_(F))

where TxPwr_(F) is a transmission power for device 202 to successfullyaccess serving access point 204, PL_(F) is a pathloss to serving accesspoint 204 measured by device 202, RoT is an RoT at the serving accesspoint 204, and No_(F) is the noise floor at the serving access point204. In one example, the noise floor can be predetermined and/orreceived in a configuration (e.g., from an access point managementserver, and/or the like).

In addition, interference caused to an access point, such as accesspoint 206, can be negligible, so as not to impact the access point 206and/or devices communicating therewith:

TxPwr_(F)−PL_(M)<No_(M)−Δ_(M)

where PL_(M) is a pathloss to access point 206 measured by device 202,No_(M) is a noise floor of access point 206, and Δ_(M) is a maximuminterference level with respect to the noise floor of access point.Combining these formulas yields:

RoT<(PL_(M)−PL_(F))+(No_(M)−No_(F)−γ) _(RACH)−Δ_(M)

and RoT threshold determining component 214 can compute an upper boundRoT threshold as:

RoT_(bound) _(—) ₁=Func1(PL_(M)−PL_(F)+(No) _(M)−No_(F))−γ_(RACH)−Δ_(M)

where pathloss measuring component 208 measures, and pathloss reportingcomponent 210 reports, PL_(M) and PL_(F) to serving access point 204,RoT threshold determining component 214 obtains No_(M) and No_(F) froman access point management server and/or access point 206, and RoTthreshold determining component 214 computes γ_(RACH) as shown above andobtains Δ_(M) as a fixed value (e.g., from an access point managementserver or other core network component, a configuration, and/or thelike). In addition, Func1 can be substantially any function ofPL_(M)−PL_(F), such as a minimum function, a percentile distribution(e.g., 10th percentile), etc., which can be configured by RoT thresholddetermining component 214 (e.g., based on a hardcoded configuration, aconfiguration received from one or more network components, etc.).

In another example, where multiple access points are present in thevicinity of serving access point 204 and potentially interfered, theupper bound RoT threshold can be determined as:

${RoT}_{{{bound}\_}1} = {{\min\limits_{k}\left( {{Func}\; 1\left( {{PL}_{M,k} - {PL}_{F}} \right)} \right)} + \left( {{No}_{M} - {No}_{F}} \right) - \gamma_{RACH} - \Delta_{M}}$

where k is an index of a respective access point (e.g., a macrocell,femtocell, picocell, etc. access point). In addition, however, device202 can access serving access point 204 under a constraint of a maximumtransmit power, which can be set by the serving access point 204:)

γ_(FACH)<Max_TxPwr_(F)−PL_(F)−(RoT+No_(F))

where Max TxPwr is the maximum transmit power, which can be received orotherwise determined by parameter receiving component 212. This canyield another upper bound RoT threshold that RoT threshold determiningcomponent 214 can compute:

RoT_(bound) _(—) ₂=Max_TxPwr_(F)−Func2(PL_(F))−γ_(RACH)−No_(F)

where Func2(PL_(F)) is a function on statistics of PL_(F) at a pluralityof device locations (e.g., a minimum function, percentile distribution,etc.). Thus, RoT threshold determining component 214, in an example, cancompute the RoT threshold for serving access point as:

RoT_(thres)=min(RoT_(bound) _(—) ₁, RoT_(bound) _(—) ₂)

For example, the various pathloss measurements discussed above can beperformed by the device 202 and/or NLM component 218 periodically (e.g.,based on one or more timers), upon request from serving access point 204(e.g., as part of a training period indicated by serving access point204), and/or the like. RoT threshold determining component 214, asdescribed, can receive the pathloss measurements and accordinglydetermine a RoT threshold. In one example, the pathloss measurements forPL_(M,k)−PL_(F), statistics of PL_(F), etc., can be computed using atraining period during which one or more devices report pathlossmeasurements. For example, upon initialization or otherwise (e.g., basedon an event or other trigger), serving access point 204 can determinedownlink transmit power based on parameters detected of other accesspoints within the vicinity, such as access point 206 (e.g., receivedsignal strength, broadcasted system information, and/or the like), andcan accordingly determine a downlink coverage area based on theparameters. RoT threshold determining component 214 can also set aninitial RoT threshold based on NLM component 218 measuring a pathloss tothe one or more access points, as described.

Subsequently, in this example, serving access point 204 can enter thetraining period to request pathloss measurements from one or moredevices, such as device 202, to one or more access points, such asaccess point 206. In one example, NLM component 218 can have collectedidentifiers of serving access points (e.g., primary scrambling codes(PSC)) upon initially measuring to determine downlink transmit power, asdescribed above. Pathloss difference computing component 220 can requestthe pathloss measurements from the devices, such as device 202 and canaccordingly specify the identifiers to the devices. The devices, such asdevice 202, can utilize pathloss measuring components, such as pathlossmeasuring component 208, to measure pathloss to one or more of theidentified access points. In addition, where pathloss measuringcomponent 208 encounters additional access points, pathloss reportingcomponent 210 can report the pathloss to serving access point 204, andpathloss difference computing component 220 can add identifiers of theadditional access points to the list of determined identifiers.

Once the pathloss measurements are gathered from the devices, such asdevice 202, to the one or more access points, such as access point 206,pathloss difference computing component 220 can generate a pathlossdifference report or cumulative density function (CDF) for each accesspoint for which a pathloss measurement is received. For example, foreach pathloss measurement for serving access point 204, PL_(F), reportedby a device, pathloss difference computing component 220 can locate akth pathloss sample to another access point, PL_(M,k), by the devicereported at the closest time and compute the difference PL_(M,k)−PL_(F).Thus, pathloss difference computing component 220 can compute a set ofPL_(M,k)−PL_(F) for each reported PL_(F), and can construct acorresponding pathloss difference CDF. In another example, pathlossdifference computing component 220 can construct the CDF based on thePL_(F) samples reported during the training period. As described, RoTthreshold determining component 214 can utilize the pathloss differenceCDF in determining a RoT threshold (e.g., by using the pathloss CDF inFunc1 or Func2, shown above).

Referring to FIG. 3, an example wireless communication system 300 isillustrated for generating a pathloss difference CDF. System 300comprises a device 302 that communicates with an access point 304 toreceive access to a wireless network. System 300 also comprises anaccess point 206, with which device 302 can potentially interfere (whichcan include interfering with devices communicating with access point206) while transmitting signals to access point 304. In this regard, forexample, access point 304 and/or access point 206 can be deployed withina vicinity of one another. As described, device 302 can be a UE, modem,etc., access point 304 and/or access point 206 can each be a macrocell,femtocell, or picocell access point, etc.

Device 302 can comprise a pathloss measuring component 208 fordetermining a pathloss to one or more access points, a pathlossreporting component 210 for communicating the pathloss to one or moresimilar or different access points, and a measurement request receivingcomponent 306 for obtaining a request from an access point to providepathloss measurements corresponding to one or more access points.

Access point 304 comprises a parameter receiving component 212 forobtaining one or more pathloss measurements to one or more access pointsfrom a device, a RoT threshold determining component 214 for determiningan RoT threshold for the access point 304 based at least in part on theone or more pathloss measurements, and an RoT threshold settingcomponent 216 for utilizing the RoT threshold at access point 304.Access point 304 can additionally comprise an optional co-located NLMcomponent 218 for receiving signals from one or more access points fordetermining a pathloss thereto, a pathloss difference computingcomponent 220 for determining a pathloss difference between access point304 and one or more other access points based on device measurements,and a measurement requesting component 308 for communicating a requestto one or more devices to perform one or more pathloss measurements.

According to an example, access point 304 can collect pathlossstatistics for computing a RoT threshold, as described. For example,pathloss measuring component 208 can measure pathloss to access point304, one or more neighboring access points, such as access point 206,and/or the like, and pathloss reporting component 210 can communicatethe pathloss measurements to access point 304. Parameter receivingcomponent 212 can obtain the pathloss measurements, and RoT thresholddetermining component 214 can determine a RoT threshold for access point304 based at least in part on the pathloss measurements, as describedabove. Moreover, for example, measurement requesting component 308 canrequest device 302 and/or other devices to perform one or more pathlossmeasurements to facilitate determining the RoT threshold.

In an example, measurement requesting component 308 can determine a setof access points to monitor from which a RoT threshold can be computedbased on pathloss to the set of access points from various devices tomitigate interference thereto. For example, measurement requestingcomponent 308 can utilize NLM component 218 to scan a primary scramblingcode (PSC) range, or other access point identifying range, to determineaccess points and/or related cells from which signals can be received byNLM component 218, such as access point 206.

In another example, measurement requesting component 308 can determineanother operating frequency for one or more of the determined accesspoints, and can request that the one or more devices perform aninter-frequency measurement for the one or more of the determined accesspoints over the other operating frequency (e.g., in addition oralternatively to the original operating frequency specified for the oneor more of the determined access points). This can facilitate measuringthe one or more of the determined access points where one or moredevices cannot detect signals therefrom (e.g., the pilot transmit poweris received below a threshold detection signal-to-interference ratio(SIR)) over the original operating frequency. In one example, themeasurement requesting component 308 can determine to request measuringon the other operating frequency upon not receiving measurements for theone or more of the determined access points within a given period oftime. Moreover, in an example, the other operating frequency can beadjacent to the original operating frequency of the one or more of thedetermined access points.

Once measurement requesting component 308 determines the set of accesspoints and/or operating frequencies thereof, measurement requestingcomponent 308 can configure one or more devices, such as device 302, tomeasure and report pathloss to at least a portion of access points inthe set (e.g., including access point 206) as well as to the accesspoint 304, as part of a training period. Measurement request receivingcomponent 306 can obtain the request to measure the pathloss, andpathloss measuring component 208 can accordingly receive signals from atleast the portion of the set of access points and the access point 304and measure pathloss based on the signals.

In this example, pathloss reporting component 210 can communicate themeasured pathloss to one or more access points, including access point304 and access point 206, to access point 304. It is to be appreciatedthat pathloss measuring component 208 can measure, and pathlossreporting component 210 can report, pathloss to additional access pointshaving other PSCs, and measurement requesting component 308 can add theadditional PSCs to the set of access points. Parameter receivingcomponent 212 can receive the pathloss measurements from device 302and/or additional pathloss measurements from other devices, asdescribed. In this regard, the pathloss measurements can be received forat least a portion of access points in the set of access points based ondifferent device locations. Parameter receiving component 212 canconstruct a pathloss cumulative density function (CDF), or othercombination of the pathloss measurements, for each access point in theset based at least in part on the pathloss measurements as received.Alternatively, the parameter receiving component 212 can characterizepathloss to each access point in the set of access points based at leastin part on measuring signals from the access points using NLM component218.

Once the parameter receiving component 212 obtains a number of pathlossmeasurements and determines the CDF for the portion of access points,parameter receiving component 212 can also compute a difference CDF foreach access point in the portion of access points for which pathlossmeasurements are received. For example, for each pathloss measurementreported for access point 304 from a device, PL_(F), such as device 302,parameter receiving component 212 can determine pathloss to the ithaccess point, PL_(M)(i), reported at the closest time from the specificdevice. For example, parameter receiving component 212 can evaluate ipathloss measurements reported by the device to determine the one withthe closest time, where i is the number of access points in the setmeasured by the device. Parameter receiving component 212 can computethe difference in the pathloss measurements, PL_(M)(i)−PL_(F), for eachreported PL_(F), and can accordingly construct the difference CDF.

Alternatively, where parameter receiving component 212 characterizes thepathloss difference using the NLM component 218, the parameter receivingcomponent 212 can compute the pathloss difference using the measuredpathloss of an access point in the set of access points acquired fromNLM component 218 along with an assumed pathloss of access point 304(e.g., 90 decibel (db) coverage radius based on downlink transmissionpower). In either example, RoT threshold determining component 214 candetermine an RoT threshold for access point 304 based at least in parton the difference CDF or other computed pathloss differences to accesspoints in the set of access points. For example, RoT thresholddetermining component 214 can determine the RoT threshold based at leastin part on a pathloss to an access point in the set of access pointhaving the lowest pathloss measurement, PL_(M)(i), or pathlossdifference measurement, PL_(M)(i)−PL_(F).

For example, RoT threshold determining component 214 can determine apathloss threshold for the set of access points based at least in parton the previously determined CDF or difference CDF. For example, thepathloss threshold can be determined based at least in part on one ormore reported pathloss differences in the CDF. In one example, RoTthreshold determining component 214 can determine the pathloss thresholdto be a certain percentile distribution of the pathloss differences inthe CDF (e.g., the lowest reported difference, a n-percentile of lowestreported differences, etc.). In any case, RoT threshold settingcomponent 216 can utilize the RoT threshold for the access point 304, asdescribed.

Referring to FIG. 4, an example wireless communication system 400 isillustrated for adjusting noise floor or RoT threshold of an accesspoint. System 400 comprises a device 402 that communicates with one ormore access points 404 and/or 406 to receive access to a wirelessnetwork. As described, for example, device 402 can potentially interferewith access point 406 while transmitting signals to access point 404(which can include interfering with devices communicating with accesspoint 406) and/or vice versa. In this regard, for example, access points404 and/or 406 can be deployed within a vicinity of one another. Asdescribed, device 402 can be a UE, modem, etc., access points 404 and/or406 can each be a macrocell, femtocell, or picocell access point, etc.

Access point 404 can comprise an optional NLM component 408 forreceiving signals from one or more access points, and an interferencedetermining component 410 for determining a level of interferencepotentially caused by one or more access points (e.g., based at least inpart on a transmission power thereof). Access point 404 can alsooptionally comprise a noise floor adjusting component 412 for modifyinga noise floor of access point 404 based at least in part on thedetermined potential interference, a RoT threshold adjusting component414 for modifying a RoT threshold of access point 404 based at least inpart on the determined potential interference, and/or a SHO devicerequesting component 416 for requesting a list of identifiers of one ormore devices for which one or more access points provide SHO access.

According to an example, access point 404 can transmit at a differentpower than access point 406. For example, where access point 406 servesdevice 402 and transmits at a higher power, device 402 can be physicallycloser to access point 404, but can still communicate with access point406 due to the higher transmission power. This can cause interference toaccess point 404. In an example, as part of access point 404initialization or based on one or more events or other triggers (e.g., atimer, detecting presence of an new access point, etc.), interferencedetermining component 410 can discern potential interference that can becaused by one or more neighboring access points, such as access point406, and can adjust one or more parameters of access point 404 tomitigate the potential interference.

In one example, access point 404 can obtain pilot transmission power ofaccess point 406 and/or one or more other neighboring access points. Forexample, NLM component 408 can detect signals from the one or moreneighboring access points, such as access point 406, and can determinethe downlink pilot transmission power thereof based at least in part onmeasuring the signal, processing data represented in the signal, and/orthe like. In another example, interference determining component 410 canreceive the downlink pilot transmission power of the one or moreneighboring access points from an access point management server orother core network component, etc. In any case, interference determiningcomponent 410 can accordingly determine the existence and/or amount ofpotential interference from the one or more access points. In oneexample, interference determining component 410 can determine such basedon comparing the downlink transmission powers with a downlinktransmission power of access point 404.

For example, based on the determined possible interference, noise flooradjusting component 412 can adjust the noise floor of access point 404.In one example, interference determining component 410 can determine astrongest downlink pilot transmission power received or observed by NLMcomponent 408 (e.g., in the case of single or multiple neighboringaccess points). Noise floor adjusting component 412 can adjust the noisefloor according to the following formula, for example:

XdB=max(0, Own_Pilot_TxPwr−Strongest_Pilot_TxPwr)

where Own_Pilot_TxPwr is the transmission power of access point 404, andStrongest_Pilot_TxPwr is the transmission power of the strongestneighboring access point (e.g., access point 406). For example, byraising the noise floor of access point 404, devices communicatingtherewith can increase transmission power to mitigate impact ofinterference on access point 404. In this regard, for example, accesspoint 404 can enforce the modified noise floor in communicating with oneor more devices (e.g., in a power control command to the one or moredevices based on a received power). For example, the noise flooradjusting component 412 can modify an uplink power control algorithm byadding a virtual noise power to the estimated noise plus interferencepower for pilot SNR computation. In addition, for example, the one ormore devices can inject additional noise, modify a RF frontendattenuator, etc. based on the noise floor adjustment.

In another example, noise floor adjusting component 412 can adaptivelyadjust the noise floor for access point 404 based on an estimated levelof out-of-cell interference (e.g., based on interference received fromdevice 402 when communicating with access point 406). For example,interference determining component 410 can measure or estimate a levelof interference to access point 404, which can include measuring a noiselevel during a silence interval or other period of time (e.g., using NLMcomponent 408), measuring a transmitted signal received by NLM component408 and determining a level of noise on top of the signal based on thepower used to transmit the signal from access point 404, and/or thelike. In any case, for example, noise floor adjusting component 412 canadaptively adjust the noise floor according to a formula similar to thefollowing:

YdB=max(0, min(XdB, Out_of_Cell_Intf_dB+Margin_dB))

where Out_of_Cell_Intf_dB is the measured or estimated out-of-cellinterference level, and Margin_dB is a constant value that renders theout-of-level interference insignificant based on the increased noisefloor. Thus, there is no increase in noise floor for zero estimatedout-of-cell interference to prevent unnecessarily increasing devicetransmit power in view of increasing noise floor.

In yet another example, instead of or in addition to adjusting the noisefloor, RoT threshold adjusting component 414 can modify an RoT thresholdof access point 404 according to potential or actual interference or oneor more access points as determined by interference determiningcomponent 410. In one example RoT threshold adjusting component 414 canmodify the RoT threshold of access point 404 based at least in part onthe computed XdB, shown above. For example, RoT threshold adjustingcomponent 414 can compute the RoT threshold adjustment based on thefollowing formula, or a similar formula:

${YdB} = \left\{ \begin{matrix}{0,} & {{{if}\mspace{14mu} 0} < {XdB} \leq 5} \\{3,} & {{{if}\mspace{14mu} 5} < {XdB} \leq 10} \\{6,} & {{{if}\mspace{14mu} 10} < {XdB} \leq 15} \\{9,} & {otherwise}\end{matrix} \right.$

such that the RoT threshold corresponds to XdB according to a function,which can be linear in this example, though other classes of functionscan similarly be utilized in this regard. Similarly, RoT thresholdadjusting component 414 can adjust the RoT threshold where interferencedetermining component 410 detects out-of-cell interference, as describedin one example. Furthermore, RoT threshold adjusting component 414 cancomply with a computed upper bound RoT threshold, as described in FIG. 2to limit interference to other access points in the vicinity as well.

In yet another example, device 402 can be served by access point 406 andalso can communicate user plane data with access point 404 (e.g., andaccess point 406) in SHO. In this example, access points 404 and 406 canboth control uplink transmission power of the device 402 (e.g., bycommunicating power adjustment commands thereto). In some examples,where device 402 is nearer to access point 406 but has less pathloss toaccess point 404, for example, access point 404 can adjust device 402transmission power down, while access point 406 attempts to increasetransmission power of device 402. In this example, noise floor adjustingcomponent 412 can adjust an estimated noise floor for modifying poweralgorithms for devices not served by access point 404 in SHO. Thus, forexample, SHO device requesting component 416 can request a list ofidentifiers from one or more access points, such as access point 406,corresponding to devices served by the one or more access points in SHO.

In this example, noise floor adjusting component 412 can compute a noisefloor adjustment based at least in part on an actual or possibleinterference determined by interference determining component 410. Noisefloor adjusting component 412 can then identify devices to which accesspoint 404 communicates in SHO that are served by access point 406 or theone or more other access points based on received device identifiers,and can modify an uplink power allocation to the devices, such as device402, based at least in part on the computed noise floor. Thus,communicating an increase in noise floor for access point 404 to device402 can cause device 402 to increase transmit power, which can improvecontrol channel quality between device 402 and access point 406. In thisexample, noise floor adjusting component 412 can refrain fromcommunicating the noise floor adjustment to devices served by accesspoint 404 to mitigate interference potentially caused by the devices toaccess point 406 or other access points.

Referring to FIGS. 5-9, example methodologies relating to adjusting oneor more parameters of a femtocell access point to mitigate interferenceare illustrated. While, for purposes of simplicity of explanation, themethodologies are shown and described as a series of acts, it is to beunderstood and appreciated that the methodologies are not limited by theorder of acts, as some acts may, in accordance with one or moreembodiments, occur in different orders and/or concurrently with otheracts from that shown and described herein. For example, it is to beappreciated that a methodology could alternatively be represented as aseries of interrelated states or events, such as in a state diagram.Moreover, not all illustrated acts may be required to implement amethodology in accordance with one or more embodiments.

Referring to FIG. 5, an example methodology 500 is displayed thatfacilitates determining a RoT threshold. At 502, one or more parameterscorresponding to one or more access points. For example, the one or moreparameters can correspond to radio conditions of the one or more accesspoints (e.g., pathloss measurements thereto), a location of the one ormore access points relative to the femtocell access point, and/or thelike. Moreover, in an example, the one or more parameters can thus bereceived from a NLM, one or more devices (e.g., based on a request formeasurements as part of a training period), and/or the like. Moreover,for example, the one or more parameters can relate to a maximum transmitpower, pathloss statistics, etc., as described above, and the RoTthreshold can be determined therefrom. At 504, a RoT threshold can bedetermined for the femtocell access point based at least in part on theone or more parameters. At 506, the RoT threshold can be set at thefemtocell access point. For example, this can cause one or more devicesto adjust a transmission power used to communicate with the femtocellaccess point.

Turning to FIG. 6, an example methodology 600 is displayed thatdetermines a RoT threshold for a femtocell access point. At 602, one ormore pathloss measurements to one or more access points can be received.As described, this can be based on a request for the measurements (e.g.,as part of a training period or otherwise). Moreover, the pathlossmeasurements can be received from a device, a NLM co-located in theaccess point, etc. At 604, a maximum transmit power provisioned to oneor more devices can be obtained. For example, this can be determinedfrom one or more components that provision the maximum transmit power.At 606, a RoT threshold can be determined based at least in part on theone or more pathloss measurements and the maximum transmit power. Asdescribed, RoT thresholds can be computed for each of the pathlossmeasurements and maximum transmit power, and a minimum of the two can beset as the RoT threshold.

Referring to FIG. 7, an example methodology 700 for determining a RoTthreshold is illustrated. At 702, one or more devices can be configuredto measure and report pathloss to at least a portion of a set of one ormore access points. For example, as described, a set of access pointscan be determined (e.g., from receiving a list of one or more accesspoints from a network component, device, etc., from detecting the one ormore access points via a NLM, and/or the like). In this example, arequest can be sent to the one or more devices to measure pathloss ofthe set of access points where the devices are able to receive signalstherefrom. At 704, pathloss measurements can be received from the one ormore devices to the portion of the set of one or more access points. Forexample, as described, this can include receiving power measurements orother measurements from which pathloss or similar parameters can bedetermined (e.g., a RSCP, CPICH transmit power, etc.). At 706, apathloss difference CDF can be constructed for at least the portion ofthe set of the one or more access points based on received pathlossmeasurements. As described, this can include determining pathlossmeasurements received for one or more access points in the set of accesspoints and subtracting another pathloss therefrom. At 708, an RoTthreshold can be determined based at least in part on the pathlossdifference CDF, as described above.

Turning to FIG. 8, an example methodology 800 is depicted for adjustingone or more parameters of an access point to mitigate interference. At802, a strongest transmit power of one or more access points can bedetected. For example, this can include receiving signals from one ormore access points in a vicinity (e.g., using an NLM and/or from one ormore devices) and determining which access point has the strongestsignal power. At 804, it can be determined whether the strongesttransmit power exceeds a transmit power utilized at a femtocell accesspoint. At 806, at least an estimated noise floor of the femtocell accesspoint can be adjusted based at least in part on whether the strongesttransmit power exceeds the transmit power. In one example, the estimatednoise floor can be adjusted by the amount the strongest transmit powerexceeds the transmit power. In another example, the estimated noisefloor can additionally be adjusted based on out-of-cell interference.Moreover, for example, a RoT threshold can be adjusted as well based onwhether the strongest transmit power exceeds the transmit power.

Referring to FIG. 9, an example methodology 900 that facilitatesenforcing noise floor increases on one or more devices is illustrated.At 902, identifiers of one or more devices served by one or more accesspoints in SHO can be received. For example, this can be based at leastin part on a request for such parameters. At 904, it can be determinedto increase an estimated noise floor. For example, this can be based atleast in part on detecting a transmission power at an access point thatis stronger than a utilized transmission power. Moreover, the estimatednoise floor can be specific to the one or more devices. At 906, theestimated noise floor increase can be enforced in communications withthe one or more devices. In this regard, noise floor is not increasedand enforced on served devices, but to devices served by other accesspoints that are communicated with using SHO, as described.

It will be appreciated that, in accordance with one or more aspectsdescribed herein, inferences can be made regarding computing a RoTthreshold, a noise floor adjustment, etc., and/or the like, asdescribed. As used herein, the term to “infer” or “inference” refersgenerally to the process of reasoning about or inferring states of thesystem, environment, and/or user from a set of observations as capturedvia events and/or data. Inference can be employed to identify a specificcontext or action, or can generate a probability distribution overstates, for example. The inference can be probabilistic—that is, thecomputation of a probability distribution over states of interest basedon a consideration of data and events. Inference can also refer totechniques employed for composing higher-level events from a set ofevents and/or data. Such inference results in the construction of newevents or actions from a set of observed events and/or stored eventdata, whether or not the events are correlated in close temporalproximity, and whether the events and data come from one or severalevent and data sources.

FIG. 10 is an illustration of a mobile device 1000 that facilitatesreporting pathloss measurements. Mobile device 1000 comprises a receiver1002 that receives a signal from, for instance, a receive antenna (notshown), performs typical actions on (e.g., filters, amplifies,downconverts, etc.) the received signal, and digitizes the conditionedsignal to obtain samples. Receiver 1002 can comprise a demodulator 1004that can demodulate received symbols and provide them to a processor1006 for channel estimation. Processor 1006 can be a processor dedicatedto analyzing information received by receiver 1002 and/or generatinginformation for transmission by a transmitter 1008, a processor thatcontrols one or more components of mobile device 1000, and/or aprocessor that both analyzes information received by receiver 1002,generates information for transmission by transmitter 1008, and controlsone or more components of mobile device 1000.

Mobile device 1000 can additionally comprise memory 1010 that isoperatively coupled to processor 1006 and that can store data to betransmitted, received data, information related to available channels,data associated with analyzed signal and/or interference strength,information related to an assigned channel, power, rate, or the like,and any other suitable information for estimating a channel andcommunicating via the channel. Memory 1010 can additionally storeprotocols and/or algorithms associated with estimating and/or utilizinga channel (e.g., performance based, capacity based, etc.), reportingpathloss, etc.

It will be appreciated that the data store (e.g., memory 1010) describedherein can be either volatile memory or nonvolatile memory, or caninclude both volatile and nonvolatile memory. By way of illustration,and not limitation, nonvolatile memory can include read only memory(ROM), programmable ROM (PROM), electrically programmable ROM (EPROM),electrically erasable PROM (EEPROM), or flash memory. Volatile memorycan include random access memory (RAM), which acts as external cachememory. By way of illustration and not limitation, RAM is available inmany forms such as synchronous RAM (SRAM), dynamic RAM (DRAM),synchronous DRAM (SDRAM), double data rate SDRAM (DDR SDRAM), enhancedSDRAM (ESDRAM), Synchlink DRAM (SLDRAM), and direct Rambus RAM (DRRAM).The memory 1010 of the subject systems and methods is intended tocomprise, without being limited to, these and any other suitable typesof memory.

Processor 1006 can further be optionally operatively coupled to apathloss measuring component 1012, which can be similar to pathlossmeasuring component 208, a pathloss reporting component 1014, which canbe similar to pathloss reporting component 210, and a measurementrequest receiving component 1016, which can be similar to measurementrequesting component 306. Mobile device 1000 still further comprises amodulator 1018 that modulates signals for transmission by transmitter1008 to, for instance, a base station, another mobile device, etc.Moreover, for example, mobile device 1000 can comprise multipletransmitters 1008 for multiple network interfaces, as described.Although depicted as being separate from the processor 1006, it is to beappreciated that the pathloss measuring component 1012, pathlossreporting component 1014, measurement request receiving component 1016,demodulator 1004, and/or modulator 1018 can be part of the processor1006 or multiple processors (not shown).

FIG. 11 is an illustration of a system 1100 that facilitatescommunicating with one or more devices using wireless communications.System 1100 comprises a base station 1102, which can be substantiallyany base station (e.g., a small base station, such as a femtocell,picocell, etc., mobile base station . . . ), a relay, etc., having areceiver 1110 that receives signal(s) from one or more mobile devices1104 through a plurality of receive antennas 1106 (e.g., which can be ofmultiple network technologies, as described), and a transmitter 1140that transmits to the one or more mobile devices 1104 through aplurality of transmit antennas 1108 (e.g., which can be of multiplenetwork technologies, as described). In addition, in one example,transmitter 1140 can transmit to the mobile devices 1104 over a wiredfront link. Receiver 1110 can receive information from one or morereceive antennas 1106 and is operatively associated with a demodulator1112 that demodulates received information. In addition, in an example,receiver 1110 can receive from a wired backhaul link. Demodulatedsymbols are analyzed by a processor 1114 that can be similar to theprocessor described above with regard to FIG. 10, and which is coupledto a memory 1116 that stores information related to estimating a signal(e.g., pilot) strength and/or interference strength, data to betransmitted to or received from mobile device(s) 1104 (or a disparatebase station (not shown)), and/or any other suitable information relatedto performing the various actions and functions set forth herein.

Processor 1114 is further optionally coupled to a parameter receivingcomponent 1118, which can be similar to parameter receiving component212, a RoT threshold determining component 1120, which can be similar toa RoT threshold determining component 214, a RoT threshold settingcomponent 1122, which can be similar to RoT threshold setting component216, a NLM component 1124, which can be similar to NLM components 218and/or 408, a pathloss difference component 1126, which can be similarto pathloss difference computing component 220, and/or a measurementrequesting component 1128, which can be similar to measurementrequesting component 308. Moreover, for example, processor 1114 can alsooptionally be coupled to an interference determining component 1130,which can be similar to interference determining component 410, a noisefloor adjusting component 1132, which can be similar to noise flooradjusting component 412, a RoT threshold adjusting component 1134, whichcan be similar to RoT threshold adjusting component 414, and/or a SHOdevice requesting component 1136, which can be similar to SHO devicerequesting component 416.

Moreover, for example, processor 1114 can modulate signals to betransmitted using modulator 1138, and transmit modulated signals usingtransmitter 1140. Transmitter 1140 can transmit signals to mobiledevices 1104 over Tx antennas 1108. Furthermore, although depicted asbeing separate from the processor 1114, it is to be appreciated that theparameter receiving component 1118, RoT threshold determining component1120, RoT threshold setting component 1122, NLM component 1124, pathlossdifference computing component 1126, measurement requesting component1128, interference determining component 1130, noise floor adjustingcomponent 1132, RoT threshold adjusting component 1134, SHO devicerequesting component 1136, demodulator 1112, and/or modulator 1138 canbe part of the processor 1114 or multiple processors (not shown), and/orstored as instructions in memory 1116 for execution by processor 1114.

With reference to FIG. 12, illustrated is a system 1200 that determinesa RoT threshold. For example, system 1200 can reside at least partiallywithin an access point, etc. It is to be appreciated that system 1200 isrepresented as including functional blocks, which can be functionalblocks that represent functions implemented by a processor, software, orcombination thereof (e.g., firmware). System 1200 includes a logicalgrouping 1202 of electrical components that can act in conjunction. Forinstance, logical grouping 1202 can include an electrical component forreceiving one or more parameters corresponding to the one or more accesspoints 1204. As described, for example, the one or more parameters cancorrespond to pathloss measurements to the one or more access points, alocation of the one or more access points (e.g., absolute or relative tothe femtocell access point or other points of reference), etc.

Further, logical grouping 1202 can comprise an electrical component fordetermining a RoT threshold for the femtocell access point based atleast in part on the one or more parameters 1206. For example, the RoTthreshold can be determined to mitigate interference to the one or moredevices, as described above. Moreover, logical grouping 1202 cancomprise an electrical component for setting the RoT threshold at thefemtocell access point 1208. As described for example, this can causedevices communicating with the femtocell access point to decreasetransmission power, which can mitigate interference caused to one ormore other access points. In an example, electrical component 1204 cancomprise a parameter receiving component 212, as described. For example,electrical component 1206 can include a RoT threshold determiningcomponent 214, as described above. In addition, for example, electricalcomponent 1208, in an aspect, can include a RoT threshold settingcomponent 216, as described above.

Additionally, system 1200 can include a memory 1210 that retainsinstructions for executing functions associated with the electricalcomponents 1204, 1206, and 1208. While shown as being external to memory1210, it is to be understood that one or more of the electricalcomponents 1204, 1206, and 1208 can exist within memory 1210. In oneexample, electrical components 1204, 1206, and 1208 can comprise atleast one processor, or each electrical component 1204, 1206, and 1208can be a corresponding module of at least one processor. Moreover, in anadditional or alternative example, electrical components 1204, 1206, and1208 can be a computer program product comprising a computer readablemedium, where each electrical component 1204, 1206, and 1208 can becorresponding code.

With reference to FIG. 13, illustrated is a system 1300 that adjusts oneor more parameters of a femtocell access point to mitigate interference.For example, system 1300 can reside at least partially within a device,etc. It is to be appreciated that system 1300 is represented asincluding functional blocks, which can be functional blocks thatrepresent functions implemented by a processor, software, or combinationthereof (e.g., firmware). System 1300 includes a logical grouping 1302of electrical components that can act in conjunction. For instance,logical grouping 1302 can include an electrical component for detectinga strongest transmit power of one or more access points 1304. Asdescribed, for example, this can include receiving signals from one ormore neighboring access points and determining a strongest of thesignals.

Further, logical grouping 1302 can comprise an electrical component foradjusting an estimated noise floor of the femtocell access point basedat least in part on determining whether the strongest transmit powerexceeds the transmit power of the femtocell access point 1306. Asdescribed for example, electrical component 1306 can set the noise floorto the difference in the transmit powers. For example, electricalcomponent 1304 can include a interference determining component 410, asdescribed above. In addition, for example, electrical component 1306, inan aspect, can include a noise floor adjusting component 412, asdescribed above.

Additionally, system 1300 can include a memory 1308 that retainsinstructions for executing functions associated with the electricalcomponents 1304 and 1306. While shown as being external to memory 1308,it is to be understood that one or more of the electrical components1304 and 1306 can exist within memory 1308. In one example, electricalcomponents 1304 and 1306 can comprise at least one processor, or eachelectrical component 1304 and 1306 can be a corresponding module of atleast one processor. Moreover, in an additional or alternative example,electrical components 1304 and 1306 can be a computer program productcomprising a computer readable medium, where each electrical component1304 and 1306 can be corresponding code.

Referring now to FIG. 14, a wireless communication system 1400 isillustrated in accordance with various embodiments presented herein.System 1400 comprises a base station 1402 that can include multipleantenna groups. For example, one antenna group can include antennas 1404and 1406, another group can comprise antennas 1408 and 1410, and anadditional group can include antennas 1412 and 1414. Two antennas areillustrated for each antenna group; however, more or fewer antennas canbe utilized for each group. Base station 1402 can additionally include atransmitter chain and a receiver chain, each of which can in turncomprise a plurality of components associated with signal transmissionand reception (e.g., processors, modulators, multiplexers, demodulators,demultiplexers, antennas, etc.), as is appreciated.

Base station 1402 can communicate with one or more mobile devices suchas mobile device 1416 and mobile device 1422; however, it is to beappreciated that base station 1402 can communicate with substantiallyany number of mobile devices similar to mobile devices 1416 and 1422.Mobile devices 1416 and 1422 can be, for example, cellular phones, smartphones, laptops, handheld communication devices, handheld computingdevices, satellite radios, global positioning systems, PDAs, and/or anyother suitable device for communicating over wireless communicationsystem 1400. As depicted, mobile device 1416 is in communication withantennas 1412 and 1414, where antennas 1412 and 1414 transmitinformation to mobile device 1416 over a forward link 1418 and receiveinformation from mobile device 1416 over a reverse link 1420. Moreover,mobile device 1422 is in communication with antennas 1404 and 1406,where antennas 1404 and 1406 transmit information to mobile device 1422over a forward link 1424 and receive information from mobile device 1422over a reverse link 1426. In a frequency division duplex (FDD) system,forward link 1418 can utilize a different frequency band than that usedby reverse link 1420, and forward link 1424 can employ a differentfrequency band than that employed by reverse link 1426, for example.Further, in a time division duplex (TDD) system, forward link 1418 andreverse link 1420 can utilize a common frequency band and forward link1424 and reverse link 1426 can utilize a common frequency band.

Each group of antennas and/or the area in which they are designated tocommunicate can be referred to as a sector of base station 1402. Forexample, antenna groups can be designed to communicate to mobile devicesin a sector of the areas covered by base station 1402. In communicationover forward links 1418 and 1424, the transmitting antennas of basestation 1402 can utilize beamforming to improve signal-to-noise ratio offorward links 1418 and 1424 for mobile devices 1416 and 1422. Also,while base station 1402 utilizes beamforming to transmit to mobiledevices 1416 and 1422 scattered randomly through an associated coverage,mobile devices in neighboring cells can be subject to less interferenceas compared to a base station transmitting through a single antenna toall its mobile devices. Moreover, mobile devices 1416 and 1422 cancommunicate directly with one another using a peer-to-peer or ad hoctechnology as depicted. According to an example, system 1400 can be amultiple-input multiple-output (MIMO) communication system. In addition,for example, base station 1402 can set a RoT threshold, noise floor, orother parameters so as not to interfere with other access points (notshown) based on one or more pathloss measurements to one or more accesspoints, detected out-of-cell interference, etc., as described.

FIG. 15 shows an example wireless communication system 1500. Thewireless communication system 1500 depicts one base station 1510 and onemobile device 1550 for sake of brevity. However, it is to be appreciatedthat system 1500 can include more than one base station and/or more thanone mobile device, wherein additional base stations and/or mobiledevices can be substantially similar or different from example basestation 1510 and mobile device 1550 described below. In addition, it isto be appreciated that base station 1510 and/or mobile device 1550 canemploy the systems (FIGS. 1-4 and 11-14), mobile devices, (FIG. 10),and/or methods (FIGS. 5-9) described herein to facilitate wirelesscommunication there between. For example, components or functions of thesystems and/or methods described herein can be part of a memory 1532and/or 1572 or processors 1530 and/or 1570 described below, and/or canbe executed by processors 1530 and/or 1570 to perform the disclosedfunctions.

At base station 1510, traffic data for a number of data streams isprovided from a data source 1512 to a transmit (TX) data processor 1514.According to an example, each data stream can be transmitted over arespective antenna. TX data processor 1514 formats, codes, andinterleaves the traffic data stream based on a particular coding schemeselected for that data stream to provide coded data.

The coded data for each data stream can be multiplexed with pilot datausing orthogonal frequency division multiplexing (OFDM) techniques.Additionally or alternatively, the pilot symbols can be frequencydivision multiplexed (FDM), time division multiplexed (TDM), or codedivision multiplexed (CDM). The pilot data is typically a known datapattern that is processed in a known manner and can be used at mobiledevice 1550 to estimate channel response. The multiplexed pilot andcoded data for each data stream can be modulated (e.g., symbol mapped)based on a particular modulation scheme (e.g., binary phase-shift keying(BPSK), quadrature phase-shift keying (QPSK), M-phase-shift keying(M-PSK), M-quadrature amplitude modulation (M-QAM), etc.) selected forthat data stream to provide modulation symbols. The data rate, coding,and modulation for each data stream can be determined by instructionsperformed or provided by processor 1530.

The modulation symbols for the data streams can be provided to a TX MIMOprocessor 1520, which can further process the modulation symbols (e.g.,for OFDM). TX MIMO processor 1520 then provides N_(T) modulation symbolstreams to N_(T) transmitters (TMTR) 1522 a through 1522 t. In variousembodiments, TX MIMO processor 1520 applies beamforming weights to thesymbols of the data streams and to the antenna from which the symbol isbeing transmitted.

Each transmitter 1522 receives and processes a respective symbol streamto provide one or more analog signals, and further conditions (e.g.,amplifies, filters, and upconverts) the analog signals to provide amodulated signal suitable for transmission over the MIMO channel.Further, N_(T) modulated signals from transmitters 1522 a through 1522 tare transmitted from N_(T) antennas 1524 a through 1524 t, respectively.

At mobile device 1550, the transmitted modulated signals are received byN_(R) antennas 1552 a through 1552 r and the received signal from eachantenna 1552 is provided to a respective receiver (RCVR) 1554 a through1554 r. Each receiver 1554 conditions (e.g., filters, amplifies, anddownconverts) a respective signal, digitizes the conditioned signal toprovide samples, and further processes the samples to provide acorresponding “received” symbol stream.

An RX data processor 1560 can receive and process the N_(R) receivedsymbol streams from N_(R) receivers 1554 based on a particular receiverprocessing technique to provide N_(T) “detected” symbol streams. RX dataprocessor 1560 can demodulate, deinterleave, and decode each detectedsymbol stream to recover the traffic data for the data stream. Theprocessing by RX data processor 1560 is complementary to that performedby TX MIMO processor 1520 and TX data processor 1514 at base station1510.

The reverse link message can comprise various types of informationregarding the communication link and/or the received data stream. Thereverse link message can be processed by a TX data processor 1538, whichalso receives traffic data for a number of data streams from a datasource 1536, modulated by a modulator 1580, conditioned by transmitters1554 a through 1554 r, and transmitted back to base station 1510.

At base station 1510, the modulated signals from mobile device 1550 arereceived by antennas 1524, conditioned by receivers 1522, demodulated bya demodulator 1540, and processed by a RX data processor 1542 to extractthe reverse link message transmitted by mobile device 1550. Further,processor 1530 can process the extracted message to determine whichprecoding matrix to use for determining the beamforming weights.

Processors 1530 and 1570 can direct (e.g., control, coordinate, manage,etc.) operation at base station 1510 and mobile device 1550,respectively. Respective processors 1530 and 1570 can be associated withmemory 1532 and 1572 that store program codes and data. Processors 1530and 1570 can determine RoT thresholds, noise floor adjustments, pathlossmeasurements, and/or the like, as described.

FIG. 16 illustrates a wireless communication system 1600, configured tosupport a number of users, in which the teachings herein may beimplemented. The system 1600 provides communication for multiple cells1602, such as, for example, macro cells 1602A-1602G, with each cellbeing serviced by a corresponding access node 1604 (e.g., access nodes1604A-1604G). As shown in FIG. 16, access terminals 1606 (e.g., accessterminals 1606A-1606L) can be dispersed at various locations throughoutthe system over time. Each access terminal 1606 can communicate with oneor more access nodes 1604 on a forward link (FL) and/or a reverse link(RL) at a given moment, depending upon whether the access terminal 1606is active and whether it is in soft handoff, for example. The wirelesscommunication system 1600 can provide service over a large geographicregion.

FIG. 17 illustrates an exemplary communication system 1700 where one ormore femto nodes are deployed within a network environment.Specifically, the system 1700 includes multiple femto nodes 1710A and1710B (e.g., femtocell nodes or H(e)NB) installed in a relatively smallscale network environment (e.g., in one or more user residences 1730).Each femto node 1710 can be coupled to a wide area network 1740 (e.g.,the Internet) and a mobile operator core network 1750 via a digitalsubscriber line (DSL) router, a cable modem, a wireless link, or otherconnectivity means (not shown). As will be discussed below, each femtonode 1710 can be configured to serve associated access terminals 1720(e.g., access terminal 1720A) and, optionally, alien access terminals1720 (e.g., access terminal 1720B). In other words, access to femtonodes 1710 can be restricted such that a given access terminal 1720 canbe served by a set of designated (e.g., home) femto node(s) 1710 but maynot be served by any non- designated femto nodes 1710 (e.g., aneighbor's femto node).

FIG. 18 illustrates an example of a coverage map 1800 where severaltracking areas 1802 (or routing areas or location areas) are defined,each of which includes several macro coverage areas 1804. Here, areas ofcoverage associated with tracking areas 1802A, 1802B, and 1802C aredelineated by the wide lines and the macro coverage areas 1804 arerepresented by the hexagons. The tracking areas 1802 also include femtocoverage areas 1806. In this example, each of the femto coverage areas1806 (e.g., femto coverage area 1806C) is depicted within a macrocoverage area 1804 (e.g., macro coverage area 1804B). It should beappreciated, however, that a femto coverage area 1806 may not lieentirely within a macro coverage area 1804. In practice, a large numberof femto coverage areas 1806 can be defined with a given tracking area1802 or macro coverage area 1804. Also, one or more pico coverage areas(not shown) can be defined within a given tracking area 1802 or macrocoverage area 1804.

Referring again to FIG. 17, the owner of a femto node 1710 can subscribeto mobile service, such as, for example, 3G mobile service, offeredthrough the mobile operator core network 1750. In addition, an accessterminal 1720 can be capable of operating both in macro environments andin smaller scale (e.g., residential) network environments. Thus, forexample, depending on the current location of the access terminal 1720,the access terminal 1720 can be served by an access node 1760 or by anyone of a set of femto nodes 1710 (e.g., the femto nodes 1710A and 1710Bthat reside within a corresponding user residence 1730). For example,when a subscriber is outside his home, he is served by a standard macrocell access node (e.g., node 1760) and when the subscriber is at home,he is served by a femto node (e.g., node 1710A). Here, it should beappreciated that a femto node 1710 can be backward compatible withexisting access terminals 1720.

A femto node 1710 can be deployed on a single frequency or, in thealternative, on multiple frequencies. Depending on the particularconfiguration, the single frequency or one or more of the multiplefrequencies can overlap with one or more frequencies used by a macrocell access node (e.g., node 1760). In some aspects, an access terminal1720 can be configured to connect to a preferred femto node (e.g., thehome femto node of the access terminal 1720) whenever such connectivityis possible. For example, whenever the access terminal 1720 is withinthe user's residence 1730, it can communicate with the home femto node1710.

In some aspects, if the access terminal 1720 operates within the mobileoperator core network 1750 but is not residing on its most preferrednetwork (e.g., as defined in a preferred roaming list), the accessterminal 1720 can continue to search for the most preferred network(e.g., femto node 1710) using a Better System Reselection (BSR), whichcan involve a periodic scanning of available systems to determinewhether better systems are currently available, and subsequent effortsto associate with such preferred systems. Using an acquisition tableentry (e.g., in a preferred roaming list), in one example, the accessterminal 1720 can limit the search for specific band and channel. Forexample, the search for the most preferred system can be repeatedperiodically. Upon discovery of a preferred femto node, such as femtonode 1710, the access terminal 1720 selects the femto node 1710 forcamping within its coverage area.

A femto node can be restricted in some aspects. For example, a givenfemto node can only provide certain services to certain accessterminals. In deployments with so-called restricted (or closed)association, a given access terminal can only be served by the macrocell mobile network and a defined set of femto nodes (e.g., the femtonodes 1710 that reside within the corresponding user residence 1730). Insome implementations, a femto node can be restricted to not provide, forat least one access terminal, at least one of: signaling, data access,registration, paging, or service.

In some aspects, a restricted femto node (which can also be referred toas a Closed Subscriber Group H(e)NB) is one that provides service to arestricted provisioned set of access terminals. This set can betemporarily or permanently extended as necessary. In some aspects, aClosed Subscriber Group (CSG) can be defined as the set of access nodes(e.g., femto nodes) that share a common access control list of accessterminals. A channel on which all femto nodes (or all restricted femtonodes) in a region operate can be referred to as a femto channel.

Various relationships can thus exist between a given femto node and agiven access terminal. For example, from the perspective of an accessterminal, an open femto node can refer to a femto node with norestricted association. A restricted femto node can refer to a femtonode that is restricted in some manner (e.g., restricted for associationand/or registration). A home femto node can refer to a femto node onwhich the access terminal is authorized to access and operate on. Aguest femto node can refer to a femto node on which an access terminalis temporarily authorized to access or operate on. An alien femto nodecan refer to a femto node on which the access terminal is not authorizedto access or operate on, except for perhaps emergency situations (e.g.,911 calls).

From a restricted femto node perspective, a home access terminal canrefer to an access terminal that authorized to access the restrictedfemto node. A guest access terminal can refer to an access terminal withtemporary access to the restricted femto node. An alien access terminalcan refer to an access terminal that does not have permission to accessthe restricted femto node, except for perhaps emergency situations, forexample, 911 calls (e.g., an access terminal that does not have thecredentials or permission to register with the restricted femto node).

For convenience, the disclosure herein describes various functionalityin the context of a femto node. It should be appreciated, however, thata pico node can provide the same or similar functionality as a femtonode, but for a larger coverage area. For example, a pico node can berestricted, a home pico node can be defined for a given access terminal,and so on.

A wireless multiple-access communication system can simultaneouslysupport communication for multiple wireless access terminals. Asmentioned above, each terminal can communicate with one or more basestations via transmissions on the forward and reverse links. The forwardlink (or downlink) refers to the communication link from the basestations to the terminals, and the reverse link (or uplink) refers tothe communication link from the terminals to the base stations. Thiscommunication link can be established via a single-in-single-out system,a MIMO system, or some other type of system.

The various illustrative logics, logical blocks, modules, components,and circuits described in connection with the embodiments disclosedherein may be implemented or performed with a general purpose processor,a digital signal processor (DSP), an application specific integratedcircuit (ASIC), a field programmable gate array (FPGA) or otherprogrammable logic device, discrete gate or transistor logic, discretehardware components, or any combination thereof designed to perform thefunctions described herein. A general-purpose processor may be amicroprocessor, but, in the alternative, the processor may be anyconventional processor, controller, microcontroller, or state machine. Aprocessor may also be implemented as a combination of computing devices,e.g., a combination of a DSP and a microprocessor, a plurality ofmicroprocessors, one or more microprocessors in conjunction with a DSPcore, or any other such configuration. Additionally, at least oneprocessor may comprise one or more modules operable to perform one ormore of the steps and/or actions described above. An exemplary storagemedium may be coupled to the processor, such that the processor can readinformation from, and write information to, the storage medium. In thealternative, the storage medium may be integral to the processor.Further, in some aspects, the processor and the storage medium mayreside in an ASIC. Additionally, the ASIC may reside in a user terminal.In the alternative, the processor and the storage medium may reside asdiscrete components in a user terminal.

In one or more aspects, the functions, methods, or algorithms describedmay be implemented in hardware, software, firmware, or any combinationthereof. If implemented in software, the functions may be stored ortransmitted as one or more instructions or code on a computer-readablemedium, which may be incorporated into a computer program product.Computer-readable media includes both computer storage media andcommunication media including any medium that facilitates transfer of acomputer program from one place to another. A storage medium may be anyavailable media that can be accessed by a computer. By way of example,and not limitation, such computer-readable media can comprise RAM, ROM,EEPROM, CD-ROM or other optical disk storage, magnetic disk storage orother magnetic storage devices, or any other medium that can be used tocarry or store desired program code in the form of instructions or datastructures and that can be accessed by a computer. Also, substantiallyany connection may be termed a computer-readable medium. For example, ifsoftware is transmitted from a website, server, or other remote sourceusing a coaxial cable, fiber optic cable, twisted pair, digitalsubscriber line (DSL), or wireless technologies such as infrared, radio,and microwave, then the coaxial cable, fiber optic cable, twisted pair,DSL, or wireless technologies such as infrared, radio, and microwave areincluded in the definition of medium. Disk and disc, as used herein,includes compact disc (CD), laser disc, optical disc, digital versatiledisc (DVD), floppy disk and blu-ray disc where disks usually reproducedata magnetically, while discs usually reproduce data optically withlasers. Combinations of the above should also be included within thescope of computer-readable media.

While the foregoing disclosure discusses illustrative aspects and/orembodiments, it should be noted that various changes and modificationscould be made herein without departing from the scope of the describedaspects and/or embodiments as defined by the appended claims.Furthermore, although elements of the described aspects and/orembodiments may be described or claimed in the singular, the plural iscontemplated unless limitation to the singular is explicitly stated.Additionally, all or a portion of any aspect and/or embodiment may beutilized with all or a portion of any other aspect and/or embodiment,unless stated otherwise.

1. A method for setting a rise-over-thermal (RoT) threshold for afemtocell access point, comprising: receiving one or more parameterscorresponding to one or more access points; determining a RoT thresholdfor the femtocell access point based at least in part on the one or moreparameters; and setting the RoT threshold at the femtocell access point.2. The method of claim 1, wherein the receiving the one or moreparameters comprises obtaining a first pathloss measurement of at leastone device to the femtocell access point, and obtaining a secondpathloss measurement of the at least one device to a second accesspoint.
 3. The method of claim 2, wherein the receiving the one or moreparameters comprises obtaining additional first pathloss measurementsfrom at least another device to the femtocell access point, andobtaining additional second pathloss measurements from the at leastanother device to the second access point, and wherein the determiningthe RoT threshold is further based at least in part on a function of adifference between the additional first pathloss measurements and theadditional second pathloss measurements.
 4. The method of claim 2,wherein the receiving the one or more parameters further comprisesobtaining one or more additional pathloss measurements of the at leastone device to one or more additional access points, and wherein thedetermining the RoT is based at least in part on a function of adifference between the first pathloss measurement and a minimum of thesecond pathloss measurement and the one or more additional pathlossmeasurements.
 5. The method of claim 2, wherein the at least one deviceis a network listening module co-located within the femtocell accesspoint.
 6. The method of claim 2, further comprising configuring the atleast one device to report at least the first pathloss measurement andthe second pathloss measurement as part of a training period.
 7. Themethod of claim 1, further comprising: determining a maximum transmitpower for devices communicating with the femtocell access point; anddetermining another RoT threshold based at least in part on the maximumtransmit power.
 8. The method of claim 7, wherein the setting the RoTthreshold comprises setting the RoT threshold as a minimum of the RoTthreshold and the another RoT threshold.
 9. The method of claim 1,wherein the receiving the one or more parameters comprises receiving alocation of the femtocell access point within a macrocell, and thedetermining the RoT threshold is based at least in part on a distancecomputed between the femtocell access point and one or more other accesspoints within the macrocell.
 10. An apparatus for setting arise-over-thermal (RoT) threshold for a femtocell access point,comprising: at least one processor configured to: receive one or moreparameters corresponding to one or more access points; determine a RoTthreshold for the femtocell access point based at least in part on theone or more parameters; and set the RoT threshold at the femtocellaccess point; and a memory coupled to the at least one processor. 11.The apparatus of claim 10, wherein the one or more parameters comprise afirst pathloss measurement of at least one device to the femtocellaccess point, and a second pathloss measurement of the at least onedevice to a second access point.
 12. The apparatus of claim 11, whereinthe one or more parameters comprise an additional first pathlossmeasurements from at least another device to the femtocell access point,and an additional second pathloss measurements from the at least anotherdevice to the second access point, and wherein the at least oneprocessor determines the RoT threshold further based at least in part ona function of a difference between the additional first pathlossmeasurements and the additional second pathloss measurements.
 13. Theapparatus of claim 11, wherein the at least one processor is furtherconfigured to obtain one or more additional pathloss measurements of theat least one device to one or more additional access points, and whereinthe one or more parameters comprise the one or more additional pathlossmeasurements.
 14. The apparatus of claim 11, wherein the at least onedevice is a network listening module co-located at the femtocell accesspoint.
 15. An apparatus for setting a rise-over-thermal (RoT) thresholdfor a femtocell access point, comprising: means for receiving one ormore parameters corresponding to one or more access points; means fordetermining a RoT threshold for the femtocell access point based atleast in part on the one or more parameters; and means for setting theRoT threshold at the femtocell access point.
 16. The apparatus of claim15, wherein the one or more parameters comprise a first pathlossmeasurement of at least one device to the femtocell access point and asecond pathloss measurement of the at least one device to a secondaccess point.
 17. The apparatus of claim 16, wherein the one or moreparameters comprise an additional first pathloss measurements from atleast another device to the femtocell access point, and an additionalsecond pathloss measurements from the at least another device to thesecond access point, and wherein the means for determining determinesthe RoT threshold further based at least in part on a function of adifference between the additional first pathloss measurements and theadditional second pathloss measurements.
 18. The apparatus of claim 16,wherein the means for receiving further obtains one or more additionalpathloss measurements of the at least one device to one or moreadditional femtocell access points, wherein the one or more parametersfurther comprise the one or more additional pathloss measurements. 19.The apparatus of claim 16, further comprising means for processing oneor more signals from the first or the second access point, wherein theat least one device comprises the means for processing.
 20. A computerprogram product for setting a rise-over-thermal (RoT) threshold for afemtocell access point, comprising: a computer-readable medium,comprising: code for causing at least one computer to receive one ormore parameters corresponding to one or more access points; code forcausing the at least one computer to determine a RoT threshold for thefemtocell access point based at least in part on the one or moreparameters; and code for causing the at least one computer to set theRoT threshold at the femtocell access point.
 21. The computer programproduct of claim 20, wherein the one or more parameters comprise a firstpathloss measurement of at least one device to the femtocell accesspoint, and a second pathloss measurement of the at least one device to asecond access point.
 22. The computer program product of claim 21,wherein the one or more parameters comprise an additional first pathlossmeasurements from at least another device to the femtocell access point,and an additional second pathloss measurements from the at least anotherdevice to the second access point, and wherein the code for causing theat least one computer to determine determines the RoT threshold furtherbased at least in part on a function of a difference between theadditional first pathloss measurements and the additional secondpathloss measurements.
 23. The computer program product of claim 21,wherein the computer-readable medium further comprises code for causingthe at least one computer to obtain one or more additional pathlossmeasurements of the at least one device to one or more additional accesspoints, and wherein the one or more parameters comprise the one or moreadditional pathloss measurements.
 24. The computer program product ofclaim 21, wherein the at least one device is a network listening moduleco-located at the femtocell access point.
 25. An apparatus for setting arise-over-thermal (RoT) threshold for a femtocell access point,comprising: a parameter receiving component for receiving one or moreparameters corresponding to one or more access points; a RoT thresholddetermining component for determining a RoT threshold for the femtocellaccess point based at least in part on the one or more parameters; and aRoT threshold setting component for setting the RoT threshold at thefemtocell access point.
 26. The apparatus of claim 25, wherein the oneor more parameters comprise a first pathloss measurement of at least onedevice to the femtocell access point and a second pathloss measurementof the at least one device to a second access point, wherein the one ormore parameters comprise the first pathloss measurement and the secondpathloss measurement.
 27. The apparatus of claim 26, wherein the one ormore parameters comprise an additional first pathloss measurements fromat least another device to the femtocell access point, and an additionalsecond pathloss measurements from the at least another device to thesecond access point, and wherein the RoT threshold determining componentdetermines the RoT threshold further based at least in part on afunction of a difference between the additional first pathlossmeasurements and the additional second pathloss measurements.
 28. Theapparatus of claim 26, wherein the parameter receiving component furtherobtains one or more additional pathloss measurements of the at least onedevice to one or more additional femtocell access points, wherein theone or more parameters further comprise the one or more additionalpathloss measurements.
 29. The apparatus of claim 26, further comprisinga network listening module (NLM) component for processing one or moresignals from the first or the second access point, wherein the at leastone device comprises the NLM component.
 30. The apparatus of claim 26,further comprising a measurement requesting component for configuringthe at least one device to report at least the first pathlossmeasurement and the second pathloss measurement as part of a trainingperiod.
 31. The apparatus of claim 25, wherein the parameter receivingcomponent determines a maximum transmit power for devices communicatingwith the femtocell access point, wherein the RoT threshold determiningcomponent determines another RoT threshold based at least in part on themaximum transmit power.
 32. The apparatus of claim 31, wherein the RoTthreshold determining component determines the RoT threshold as aminimum of the RoT threshold and the another RoT threshold.
 33. Theapparatus of claim 25, wherein the one or more parameters comprise alocation of the femtocell access point within a macrocell, and the RoTthreshold determining component determines the RoT threshold based atleast in part on a distance computed between the femtocell access pointand one or more other access points within the macrocell.
 34. A methodfor adjusting parameters of an access point based on determininginterference, comprising: detecting a strongest transmit power of one ormore access points; determining whether the strongest transmit powerexceeds a transmit power utilized at a femtocell access point; andadjusting an estimated noise floor of the femtocell access point basedat least in part on whether the strongest transmit power exceeds thetransmit power.
 35. The method of claim 34, further comprisingestimating a level of out-of-cell interference, wherein the adjustingthe estimated noise floor is further based at least in part on the levelof out-of-cell interference.
 36. The method of claim 35, wherein theestimating the level of out-of-cell interference comprises measuringnoise during a period of time.
 37. The method of claim 34, furthercomprising adjusting a rise-over-thermal threshold of the femtocellaccess point based at least in part on whether the strongest transmitpower exceeds the transmit power.
 38. The method of claim 34, whereinthe adjusting the estimated noise floor comprises adjusting theestimated noise floor of the femtocell access point for a given devicethat is served by a different access point in soft handover.
 39. Themethod of claim 38, further comprising: requesting identifiers ofdevices served by the access point in soft handover; and receiving anidentifier of the given device from the different access point based atleast in part on the request.
 40. The method of claim 34, furthercomprising enforcing the estimated noise floor for communications withthe at least one device.
 41. An apparatus for adjusting parameters of anaccess point based on determining interference, comprising: at least oneprocessor configured to: detect a strongest transmit power of one ormore access points; determine whether the strongest transmit powerexceeds a transmit power utilized at a femtocell access point; andadjust a noise floor of the femtocell access point based at least inpart on whether the strongest transmit power exceeds the transmit power;and a memory coupled to the at least one processor.
 42. The apparatus ofclaim 41, wherein the at least one processor is further configured toestimate a level of out-of-cell interference, wherein the at least oneprocessor adjusts the noise floor further based at least in part on thelevel of out-of-cell interference.
 43. The apparatus of claim 41,wherein the at least one processor is further configured to adjust arise-over-thermal threshold of the femtocell access point based at leastin part on whether the strongest transmit power exceeds the transmitpower.
 44. The apparatus of claim 41, wherein the at least one processoradjusts the noise floor of the femtocell access point for a given devicethat is served by a different access point in soft handover.
 45. Theapparatus of claim 44, wherein the at least one processor is furtherconfigured to request identifiers of device served by the access pointin soft handover and receive an identifier of the given device from thedifferent access point based at least in part on the request.
 46. Anapparatus for adjusting parameters of an access point based ondetermining interference, comprising: means for detecting a strongesttransmit power of one or more access points; and means for adjusting anoise floor of a femtocell access point based at least in part ondetermining whether the strongest transmit power exceeds a transmitpower of the femtocell access point.
 47. The apparatus of claim 46,wherein the means for detecting further estimates a level of out-of-cellinterference, and the means for adjusting adjusts the noise floorfurther based at least in part on the level of out-of-cell interference.48. The apparatus of claim 46, further comprising means for adjusting arise-over-thermal threshold of the femtocell access point based at leastin part on whether the strongest transmit power exceeds the transmitpower.
 49. The apparatus of claim 46, wherein the means for adjustingadjusts the noise floor of the femtocell access point for a given devicethat is served by a different access point in soft handover.
 50. Theapparatus of claim 49, further comprising means for requestingidentifiers of devices served by the access point in soft handover andreceiving an identifier of the given device from the different accesspoint based at least in part on the request.
 51. A computer programproduct for adjusting parameters of an access point based on determininginterference, comprising: a computer-readable medium, comprising: codefor causing at least one computer to detect a strongest transmit powerof one or more access points; code for causing the at least one computerto determine whether the strongest transmit power exceeds a transmitpower utilized at a femtocell access point; and code for causing the atleast one computer to adjust a noise floor of the femtocell access pointbased at least in part on whether the strongest transmit power exceedsthe transmit power.
 52. The computer program product of claim 51,wherein the computer-readable medium further comprises code for causingthe at least one computer to estimate a level of out-of-cellinterference, wherein the code for causing the at least one computer toadjust adjusts the noise floor further based at least in part on thelevel of out-of-cell interference.
 53. The computer program product ofclaim 51, wherein the computer-readable medium further comprises codefor causing the at least one computer to adjust a rise-over-thermalthreshold of the femtocell access point based at least in part onwhether the strongest transmit power exceeds the transmit power.
 54. Thecomputer program product of claim 51, wherein the code for causing theat least one computer to adjust adjusts the noise floor of the femtocellaccess point for a given device that is served by a different accesspoint in soft handover.
 55. The computer program product of claim 54,wherein the computer-readable medium further comprises code for causingthe at least one computer to request identifiers of device served by theaccess point in soft handover and receive an identifier of the givendevice from the different access point based at least in part on therequest.
 56. An apparatus for adjusting parameters of an access pointbased on determining interference, comprising: an interferencedetermining component for detecting a strongest transmit power of one ormore access points; and a noise floor adjusting component for adjustinga noise floor of a femtocell access point based at least in part ondetermining whether the strongest transmit power exceeds a transmitpower of the femtocell access point.
 57. The apparatus of claim 56,wherein the interference determining component further estimates a levelof out-of-cell interference, and the noise floor adjusting componentadjusts the noise floor further based at least in part on the level ofout-of-cell interference.
 58. The apparatus of claim 57, wherein theinterference determining component estimates the level of out-of-cellinterference at least in part by measuring noise during a period oftime.
 59. The apparatus of claim 56, further comprising arise-over-thermal (RoT) threshold adjusting component for adjusting aRoT threshold of the femtocell access point based at least in part onwhether the strongest transmit power exceeds the transmit power.
 60. Theapparatus of claim 56, wherein the noise floor adjusting componentadjusts the noise floor of the femtocell access point for a given devicethat is served by a different access point in soft handover.
 61. Theapparatus of claim 60, a soft handover (SHO) device requesting componentfor requesting identifiers of devices served by the access point in SHOand receiving an identifier of the given device from the differentaccess point based at least in part on the request.
 62. The apparatus ofclaim 56, wherein the noise floor adjusting component reports the noisefloor to at least one device.